Here's a number you can count on

We totally understand if you have 12 on the brain today, what with it marking that rare 12/12/12 on the calendar. But there's something special about that number that goes beyond our day planners, much less our wall clocks, rose bouquets or egg cartons.

Think of 12 as having a mathematical magic that factors into more than just your everyday dozen.

“The number 12 shows up a lot in ancient and medieval weights and measurement systems. Probably even dates back to the Mesopotamian times,” says Mary Wagner-Krankel, chair of the mathematics department at St. Mary's University. “Most of those cultures tried to tie everything to the growing season and things of that nature. That's probably why our calendar looks the way it does.”

Then there are the number's more spiritual connections. And we don't mean numerology.

“In the Bible the significance of the number 12 is that it represents divine authority and appointment,” Wagner-Krankel says, noting that 12 is found more than 180 times in the Bible, including the number of Jesus' apostles and his age when he first appeared to the public.

Of course it's hard to resist any number that repeats three times in one date, especially if you're lovebirds. Just ask the thousands of couples who tied the knot on 7/7/07 — and 8/8/08, 9/9/09, etc.

Bexar County Clerk Gerard Rickhoff marries couples all the time. He noticed a spike in “I do's” last year for Nov. 11. (As in 11/11/11.) City Hall doesn't have any front-step nuptials planned today, but Rickhoff still expects a larger than usual number of Dec. 12 weddings for this year.

“It really awakened me to the reality that people do look at these numbers (to) ... bring some enhancement to their relationship,” Rickhoff says.

Here are a dozen more special relationships to the number 12.

In mythology and religion. The ancient Greeks worshipped 12 major gods of Olympus, plus sang the cheers of the 12 labors of Hercules. And as noted earlier, Christianity has the 12 apostles of Jesus — not to mention the 12 days of Christmas.

Judaism has the 12 sons of the Jewish forefather Jacob, who founded the 12 tribes of Israel. And followers of Shia Islam note that the prophet Muhammad has 12 successors called Imams.

Guiding principles. Alcoholics Anonymous has the Twelve Steps and Twelve Traditions to overcome addiction. The Twelve Steps guide the individual in AA, while the Twelve Traditions govern the AA group.

12 in time. Besides 12 months making a year, the number also evenly splits the day by the 12-hour clock and divides evenly into 60 minutes and 60 seconds. And for those who consult the stars with their daily calendar, there are 12 astrological signs in the Western and Chinese zodiacs.

The 12th Man at Texas A&M University. The Aggie tradition dates back to January, 2, 1922, when student E. King Gill got called out of the stands to suit up for an injury-riddled A&M football team down to 11 players. Gill never left the sidelines, and A&M went on to beat Centre College 22-14. The gesture lives on with A&M's student body representing that 12th player.

The Cowboys never forget No. 12. Before he turned joined the Dallas Cowboys in 1969, Roger Staubach wore the No. 12 on his Naval Academy jersey. The academy retired his jersey at his graduation ceremony. The Cowboys don't officially retire jersey numbers. However, the franchise has never reissued the jersey No. 12, which the Hall of Fame quarterback wore for Dallas until 1979.

San Antonio's own No. 12 in the rafters. In March, the Spurs retired Bruce Bowen's No. 12 jersey number, which hangs in the AT&T Center with the jersey numbers of six other Spurs greats.

Three times the “Angry Men.” Reginald Rose's powerful 1954 teleplay “Twelve Angry Men” was also rewritten for the stage in 1955 with the same name and then as the 1957 movie “12 Angry Men” starring Henry Fonda.

A “Dirty” dozen. The 1967 war film “The Dirty Dozen” is based on E.M. Nathanson's book of the same name, which took inspiration from a real-life WWII unit called the Filthy Thirteen.

Or “What You Will,” Will. The full title of William Shakespeare's comedy “Twelfth Night” is “Twelfth Night; or, What You Will.” The standard title “Twelfth Night” has, if you will, 12 letters.

Only 12 people have ever walked on the moon. Harrison Schmitt and Eugene Cernan, the last two astronauts to pull off the original moonwalk, did so in December 1972.

A couple of 12-pairs in the body. The human body has 12 pairs of ribs and 12 pairs of cranial nerves.

Now that's a movie marathon. “Star Trek” and “Friday the 13th” each have 12 films in their respective franchises.

René A. Guzman is a features writer for the San Antonio Express-News. He writes about geek and pop culture as well as consumer gadgets and technology, and writes a blog called Geek Speak that covers comic books, tabletop gaming and other geek culture in San Antonio and beyond. He has also written about health and fitness and other consumer topics. In addition to the Express-News, Guzman's work has appeared in the Baltimore Sun, Beaumont Enterprise, Chicago Tribune, Houston Chronicle and San Francisco Chronicle. Before joining the Express-News in December 1998, the San Antonio native co-owned a college humor magazine named Bitter, for which he wrote, designed and edited, as well as distributed at various campuses and businesses citywide.